package com.ruoyi.common.utils.sign;

import org.apache.commons.codec.binary.Base64;

import javax.crypto.Cipher;
import java.security.*;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;

public class RsaUtils {

        // Rsa 私钥
        public static String privateKey = "MIIBVAIBADANBgkqhkiG9w0BAQEFAASCAT4wggE6AgEAAkEAqhHyZfSsYourNxaY"
                + "7Nt+PrgrxkiA50efORdI5U5lsW79MmFnusUA355oaSXcLhu5xxB38SMSyP2KvuKN"
                + "PuH3owIDAQABAkAfoiLyL+Z4lf4Myxk6xUDgLaWGximj20CUf+5BKKnlrK+Ed8gA"
                + "kM0HqoTt2UZwA5E2MzS4EI2gjfQhz5X28uqxAiEA3wNFxfrCZlSZHb0gn2zDpWow"
                + "cSxQAgiCstxGUoOqlW8CIQDDOerGKH5OmCJ4Z21v+F25WaHYPxCFMvwxpcw99Ecv"
                + "DQIgIdhDTIqD2jfYjPTY8Jj3EDGPbH2HHuffvflECt3Ek60CIQCFRlCkHpi7hthh"
                + "YhovyloRYsM+IS9h/0BzlEAuO0ktMQIgSPT3aFAgJYwKpqRYKlLDVcflZFCKY7u3"
                + "UP8iWi1Qw0Y=";

        /**
         * 私钥解密
         * @param text 待解密的文本
         * @return 解密后的文本
         */
        public static String decryptByPrivateKey(String text) throws Exception
        {
            return decryptByPrivateKey(privateKey, text);
        }

        /**
         * 公钥解密
         *
         * @param publicKeyString 公钥
         * @param text 待解密的信息
         * @return 解密后的文本
         */
        public static String decryptByPublicKey(String publicKeyString, String text) throws Exception
        {
            X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(Base64.decodeBase64(publicKeyString));
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
            Cipher cipher = Cipher.getInstance("RSA");
            cipher.init(Cipher.DECRYPT_MODE, publicKey);
            byte[] result = cipher.doFinal(Base64.decodeBase64(text));
            return new String(result);
        }

        /**
         * 私钥加密
         *
         * @param privateKeyString 私钥
         * @param text 待加密的信息
         * @return 加密后的文本
         */
        public static String encryptByPrivateKey(String privateKeyString, String text) throws Exception
        {
            PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(Base64.decodeBase64(privateKeyString));
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
            Cipher cipher = Cipher.getInstance("RSA");
            cipher.init(Cipher.ENCRYPT_MODE, privateKey);
            byte[] result = cipher.doFinal(text.getBytes());
            return Base64.encodeBase64String(result);
        }

        /**
         * 私钥解密
         *
         * @param privateKeyString 私钥
         * @param text 待解密的文本
         * @return 解密后的文本
         */
        public static String decryptByPrivateKey(String privateKeyString, String text) throws Exception
        {
            PKCS8EncodedKeySpec pkcs8EncodedKeySpec5 = new PKCS8EncodedKeySpec(Base64.decodeBase64(privateKeyString));
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec5);
            Cipher cipher = Cipher.getInstance("RSA");
            cipher.init(Cipher.DECRYPT_MODE, privateKey);
            byte[] result = cipher.doFinal(Base64.decodeBase64(text));
            return new String(result);
        }

        /**
         * 公钥加密
         *
         * @param publicKeyString 公钥
         * @param text 待加密的文本
         * @return 加密后的文本
         */
        public static String encryptByPublicKey(String publicKeyString, String text) throws Exception
        {
            X509EncodedKeySpec x509EncodedKeySpec2 = new X509EncodedKeySpec(Base64.decodeBase64(publicKeyString));
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec2);
            Cipher cipher = Cipher.getInstance("RSA");
            cipher.init(Cipher.ENCRYPT_MODE, publicKey);
            byte[] result = cipher.doFinal(text.getBytes());
            return Base64.encodeBase64String(result);
        }

        /**
         * 构建RSA密钥对
         *
         * @return 生成后的公私钥信息
         */
        public static RsaKeyPair generateKeyPair() throws NoSuchAlgorithmException
        {
            KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
            keyPairGenerator.initialize(1024);
            KeyPair keyPair = keyPairGenerator.generateKeyPair();
            RSAPublicKey rsaPublicKey = (RSAPublicKey) keyPair.getPublic();
            RSAPrivateKey rsaPrivateKey = (RSAPrivateKey) keyPair.getPrivate();
            String publicKeyString = Base64.encodeBase64String(rsaPublicKey.getEncoded());
            String privateKeyString = Base64.encodeBase64String(rsaPrivateKey.getEncoded());
            return new RsaKeyPair(publicKeyString, privateKeyString);
        }

        /**
         * RSA密钥对对象
         */
        public static class RsaKeyPair
        {
            private final String publicKey;
            private final String privateKey;

            public RsaKeyPair(String publicKey, String privateKey)
            {
                this.publicKey = publicKey;
                this.privateKey = privateKey;
            }

            public String getPublicKey()
            {
                return publicKey;
            }

            public String getPrivateKey()
            {
                return privateKey;
            }
        }

}
